The invention concerns an input system for orientation in a visualization of three-dimensional data sets, as well as a method for visualization of data points of a three-dimensional data set; the invention also concerns a representation device to represent such a visualization; moreover, the invention concerns a method to operate an imaging medical examination device and a method for graphical positioning of a slice to be measured by means of an imaging medical examination device in a three-dimensional data set of a preparation measurement.
The acquisition, representation and processing of three-dimensional data sets becomes significantly more important with increasing computing capacity of modern computers, since now spatial data with high data density (i.e. high resolution) can also be acquired, displayed and processed. In modern imaging medical examination devices, the advance in the development of such devices goes directly hand in hand with the possibility of an adequate representation and evaluation of the medical data. This is, for example, the case with the large medical devices in computer tomography or magnetic resonance tomography, or in the field of ultrasound sonography. Thus, for example, the acquisition of high-resolution angiography data primarily makes possible precise medical procedures.
Until now, the representation of such three-dimensional data sets has occurred in various ways. On the one hand, two-dimensional slice images or cross-sections were shown on conventional monitors. The third dimension was indirectly shown by the possibility of the display (“riffle-throughs”) of various slices. On the other hand, there is the possibility of the perspective representation, whereby this must be calculated from the three-dimensional data sets. A virtual 3D subject shown in such a manner can then be considered from various directions via a computer-controlled rotation, meaning via a change of the perspective origin. This type of 3D representation can be transmitted to projection systems.
Another type of representation is based on what are known as 3D glasses, which effect a three-dimensional image for the observer. A further development leads to a three-dimensional representation in what is known as cyberspace. Three-dimensional data are thereby imported into a data helmet with data glasses. A spatial effect is conveyed to the viewer that is close to reality due to the fact that the position of the observer (given by the position of the data helmet) is taken into account in the representation of the three-dimensional data set.
Volumetric monitors take up an exceptional amount of room. An example is the 3D monitor by the company Actuality Systems that generates a real three-dimensional image of a subject to be imaged. A two-dimensional calculated image is thereby project on a rotating plane, such that a three-dimensional image exists for an observer. The application potential of such 3D monitors is, for example, in the field of the display of data acquired with the aid of medical imaging devices, or in the field of the display of complex three-dimensional structures, for example molecules. Among other things, volumetric monitors exhibit two advantages. On the one hand, the images are visible from a large range surrounding the monitor, such that a plurality of observers can simultaneously view the represented subject. This is particularly advantageous for teaching purposes. On the other hand, a 3D monitor enables the observer to focus on arbitrary points of the subject and to respectively obtain a sharp image.
For the user, it is now decisive how user-friendly it is to access virtual perspective information or real three-dimensionally represented information. Of first importance is an input device with which a data point in a data set can be selected, second the possibility to manipulate the data point, and third as advantageous as possible a representation of the manipulated 3D data set.